Title: Semicircular Rashba arc spin polarizer

Abstract

In this work, we study the generation of spin polarized currents using curved arcs of finite widths, in which the Rashba spin orbit interaction (RSOI) is present. Compared to the 1-dimensional RSOI arcs with zero widths studied previously, the finite width presents charge carriers with another degree of freedom along the transverse width of the arc, in addition to the longitudinal degree of freedom along the circumference of the arc. The asymmetry in the transverse direction due to the difference in the inner and outer radii of the arc breaks the antisymmetry of the longitudinal spin z current in a straight RSOI segment. This property can be exploited to generate spin z polarized current output from the RSOI arc by a spin unpolarized current input. The sign of the spin current can be manipulated by varying the arc dimensions.

@article{osti_22273797,
title = {Semicircular Rashba arc spin polarizer},
author = {Bin Siu, Zhuo, E-mail: a0018876@nus.edu.sg and Advanced Concepts and Nanotechnology, Data Storage Institute, DSI Building, 5 Engineering Drive 1 and Jalil, Mansoor B. A. and Ghee Tan, Seng},
abstractNote = {In this work, we study the generation of spin polarized currents using curved arcs of finite widths, in which the Rashba spin orbit interaction (RSOI) is present. Compared to the 1-dimensional RSOI arcs with zero widths studied previously, the finite width presents charge carriers with another degree of freedom along the transverse width of the arc, in addition to the longitudinal degree of freedom along the circumference of the arc. The asymmetry in the transverse direction due to the difference in the inner and outer radii of the arc breaks the antisymmetry of the longitudinal spin z current in a straight RSOI segment. This property can be exploited to generate spin z polarized current output from the RSOI arc by a spin unpolarized current input. The sign of the spin current can be manipulated by varying the arc dimensions.},
doi = {10.1063/1.4866388},
journal = {Journal of Applied Physics},
number = 17,
volume = 115,
place = {United States},
year = 2014,
month = 5
}

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